Published 4:00 am, Thursday, September 17, 1998

It's on the nose of movie stars inside dark theaters. It's on the teacher's back in algebra class. It's even starred in its own "Seinfeld" episode.

The red dot is the electronic graffiti of the 1990s. There is no easy way to escape the red dot, although city councils are passing laws against them and school principals are snatching them away.

The red dot is the beam of light produced by a battery-operated gizmo known as a laser pointer. The dot can be projected hundreds of feet. Its main appeal is that it appears to come from nowhere and that the person holding the pointer can be almost impossible to detect.

For years, laser pointers, which are about the size of a fountain pen, were expensive tools used by business leaders conducting boring seminars in dark boardrooms.

In recent months, however, the bottom has fallen out of the market. Now, laser pointers can be had for as little as $18.

The manager of one downtown San Francisco theater said she has been kicking out laser- wielding kids at a pace of about one a week.

"I don't know why they do it, maybe just the thrill of bothering somebody," said Pearl Stimmel, manager of the Regency I Theater on Van Ness Avenue.

"It usually happens at a quiet time in the

movie, when there's not enough action. I have to send in an usher. It can be very difficult to figure out in the dark who's doing it."

Stimmel said kids who are caught red-dot-handed are given the choice of checking their lasers at the door, Dodge City-style, or getting booted from the theater.

"It's a real bother," Stimmel said. "It takes one of my people away from the candy counter."

At a screening of the movie "There's Something About Mary" in San Bruno the other night, a red dot danced on the nose of star Ben Stiller for many long moments, eliciting giggles from the crowd that were not in the script.

"They called the usher," recalled one moviegoer. "The guy looked around, but they never found the person with the laser."

Some communities are fighting the red menace. A handful of towns and school boards have passed laws forbidding youths from buying or possessing laser pointers, much as youths are being prohibited from getting spray- paint cans and permanent marking pens.

Communities with such bans include Virginia Beach, Va., Westchester County, N.Y., Ocean City, Md., and Chicago Ridge, Ill. Some stores, such as Radio Shack, ban sales of laser pointers to anyone under 18.

Last winter, a fan was ejected from a New Jersey Nets basketball game for trying to distract a player with a laser.

Usually, the dots are harmless fun. San Francisco private eye Jayson Wechter has amused children at parties for years by causing the red dot to dance across the floor, where kids chase it like kittens after a pingpong ball.

Some targets of the red beam have gotten the jitters, however, assuming the dots are coming from high-tech guns with laser sights, Arnold Schwarzenegger- style.

Also annoyed by the dot was the character George, in a particularly memorable episode in the last season of the "Seinfeld" TV show, after an anonymous theater patron shined the red dot on him. The dot proceeded to follow George out of the theater and even into his car.

Not amused is the Food and Drug Administration, which has warned that staring directly into the pointers can cause eye damage. But ophthalmologists say the dangers are exaggerated.

"They're more of a nuisance than a public-health threat," said Dr. David Hwang, associate professor of ophthalmology at the University of California at San Francisco.

The battery-powered lasers do not emit enough energy to cause permanent eye damage, he said.

A typical laser pointer emits fewer than 5 milliwatts of power, whereas some medical lasers use 100 to 200 milliwatts, and some surgical lasers use roughly 500 milliwatts.

Hwang says the effect of looking momentarily into a laser pointer is like looking at a camera flashgun -- annoying, but not dangerous.

According to the FDA, laser pointers are Class II or Class III-a lasers, emitting slightly more power than lasers in CD players and computer printers but only 1 percent of the power of surgical or machine-tool lasers.

While high-end laser pointers are still fetching $200 from such adult toy stores as Sharper Image on Market Street ("Your presentations will have much more impact when you highlight each point with these new, state-of-the-art laser pointers," says the catalog), the Costco discount warehouse chain sells a Chinese-made laser pointer for $18.

Each package comes with two AA batteries and more printed warnings than a pack of cigarettes.

Now Playing:

"Danger. Avoid Direct Eye Exposure. Do not allow children to play with the pointer."

Children, however, are the hottest market share. Every grown-up who felt the need to own a laser pointer bought one long ago.

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